SOGC Infectious Diseases Committee Statement on Syphilis

Syphilis, caused by Treponema pallidum, is a sexually transmitted disease mainly acquired through oral, anal or vaginal sexual contact. Classically, it presents as a painless ulcer, with more systemic symptoms in the secondary stage. If untreated, a latency period of varying lengths precedes tertiary syphilis with pathology determined by where the spirochetes have concentrated in a given individual’s tissues. Importantly, many patients do not experience classic signs and symptoms of primary and secondary syphilis and most cases of syphilis are being detected in asymptomatic individuals or in latent stages of disease.

Rates of syphilis infection are increasing dramatically across the entire country and a number of provinces are currently experiencing a syphilis epidemic. In 2018, British Columbia reported 925 cases of infectious syphilis representing a 33% increase from 2017. In Manitoba, final syphilis counts for 2018 are estimated at 750-1000. Similar epidemiologic trends have also been reported in the east of the country, for example Ontario is reporting over 20% increase in the number of cases of syphilis for 2018 compared to 2017.

Of particular concern to prenatal care providers is the proportion of cases occurring in reproductive aged women. With a 50% increase in infectious syphilis among females 20-39 years old we are also seeing a resurgence of congenital syphilis across the country. Two cases of congenital syphilis have been documented this year in British Columbia, the first since 2013. Alberta has also reported 10 cases of congenital syphilis for 2018. In Manitoba, 10 confirmed and 9 probable cases of congenital syphilis have been reported since January 1st, 2018. In Quebec, 7 cases of congenital syphilis were reported between 2016-2018.

When a pregnant woman has syphilis (acquired either prior to or during pregnancy), it can be transmitted to the fetus. While the highest rate of vertical transmission occurs with primary and secondary syphilis, it may occur with any stage of syphilis during pregnancy leading to congenital syphilis. Congenital syphilis can cause miscarriage, stillbirth, intrauterine growth restriction, fetal hydrops, fetal malformation, and neonatal death in more than a third of cases. Moreover, if unrecognized and untreated, congenital syphilis can have important health consequences for a child’s health and development.

Congenital syphilis is preventable. Prevention can be achieved through adequate screening and antibiotic treatment during pregnancy. Routine screening for sexually transmitted infections, including syphilis, is standard of care at the first prenatal visit in Canada; however, given the current epidemiology, enhanced screening during pregnancy should be considered. If there is an outbreak declared within your province, increased screening should be considered. Please refer to your provincial public health department to determine if an outbreak has been defined.

Unfortunately, social risk factors alone often have poor sensitivity for risk of STI acquisition and may miss individuals with subtle or undisclosed risk factors. As such, local epidemiology may dictate a need for universal implementation of enhanced syphilis screening during pregnancy (e.g. at three time points for all pregnant women).

A multidisciplinary approach for both prevention and management of syphilis in pregnancy is necessary to help control the epidemic. Engagement of local public health services, particularly for patients who are having difficulty connecting with care, is important to ensure thorough partner identification, testing and treatment. Communication with pediatric and pediatric infectious diseases services for evaluation and newborn management planning is warranted for all infants born to mothers with syphilis during pregnancy. Guidance for newborn management in cases of syphilis infection during pregnancy can be found here.

It is time for increased action in order to prevent future cases of congenital syphilis. Detection and treatment of syphilis as early as possible during pregnancy is critical to preventing congenital syphilis. Education of colleagues, trainees and patients of the importance of screening for syphilis and other STIs is paramount.